Cardiac device and methods of use thereof

ABSTRACT

Devices and methods are described herein which are directed to the treatment of a patient&#39;s heart having, or one which is susceptible to heart failure, to improve diastolic function.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/640,469 filed Dec. 14, 2006, which is a continuation-in-partapplication of U.S. patent application Ser. No. 10/212,033, filed Aug.1, 2002, which is a continuation-in-part of prior U.S. patentapplication Ser. No. 09/635,511, filed on Aug. 9, 2000, which claimspriority from U.S. Provisional Patent Application No. 60/147,894 filedon Aug. 9, 1999; these applications are incorporated herein by referencein their entirety and to which applications we claim priority under 35USC §120.

INCORPORATION BY REFERENCE

All publications and patent applications mentioned in this specificationare herein incorporated by reference to the same extent as if eachindividual publication or patent application was specifically andindividually indicated to be incorporated by reference.

BACKGROUND OF THE INVENTION

Heart failure (HF) is one of the most common causes of in-hospitalmortality for patients with cardiac diseases. Heart failure is typifiedby the inability of the heart to pump enough blood to meet the body'smetabolic requirements for oxygen and nutrients leading to discrepanciesbetween myocardial oxygen supply and demand.

The left ventricle's inability to generate sufficient cardiac output,i.e. HF, is commonly associated with left ventricular systolic (emptyingof left ventricular chamber) dysfunction, but its symptoms may alsoarise as a result of diastolic (filling of left ventricular chamber)dysfunction (with or without the presence of systolic dysfunction). Theterm “diastolic dysfunction” refers to changes in ventricular diastolicproperties that have an adverse effect on ventricular diastolicpressures and ventricular filling.

An integral part of normal diastolic filling is the contribution of theleft ventricular (LV) elastic recoil forces to the LV filling. Elasticrecoil forces are generated within healthy myocardium during systolicshortening. The magnitudes of elastic recoil forces are inverselyproportional to the volume of the LV, i.e., they increase as the LVvolume decreases. Their contribution is important in early diastolebecause they allow rapid and enhanced early filling by assisting theexpansion of the left ventricle.

In a case of ventricular enlargement and/or the decrease of myocardialfunction due to hypertrophy the left ventricular elastic recoil forcesmay be diminished or nonexistent, therefore ceasing to assist earlyventricular filling and leading to an increase of the ventricularfilling pressure.

Intervention to alleviate the resultant symptoms of the physical changesdescribed above may offer great benefit to patients with heart disease.Administration of vasodilators, diuretics, sodium channel blockers, andinotropic agents have been used to reduce the number of acute events andslow the advance of disease, but cannot reverse the physical changes tothe heart. Surgical intervention can reduce the volume of the ventriclesuch that cardiac function is improved but carries high risk for thepatient. Other less invasive modes of intervention offer improvedfunction while reducing risk for the patient during and after theprocedure.

SUMMARY OF THE INVENTION

The present invention is directed to methods for the treatment of apatient's heart having, or one which is susceptible to, heart failure,in particular, a patient's heart exhibiting diastolic dysfunction. Thediastolic dysfunction may be a result of one or more conditions, forexample, reduced elastic recoil in the ventricular chamber, morespecifically the left ventricle. Diastolic dysfunction is established,for example, by measurements of various echocardiographic parameterssuch as decreased peak filling velocity and prolonged relaxation time,signs of increased filling pressure, and clinical symptoms of dyspneaand peripheral edema.

In one aspect of the invention a diastolic recoil device is providedwhich includes a membrane, a hub, preferably centrally located on thediastolic recoil device, and a radially expandable reinforcing frameformed of a plurality of ribs. For example, there may be at least 3 andup to 20 ribs, depending on the application. An elastic, resilient framemay be used. The ribs have distal ends which may be pivotally mounted tothe hub and biased outwardly or fixed to the hub, and free proximal endswhich are configured to curve or flare away from a center line axis uponexpansion of the partitioning device. Tissue penetrating proximalanchors of the free proximal ends are configured to penetrate the tissuelining at an angle 30-120 degrees to the centerline axis of thediastolic recoil device. The tissue penetrating proximal anchors of theribs may be provided with barbs, hooks, and the like which preventundesired withdrawal of the tips from the heart wall. The diastolicrecoil device and its components may be made with various sizes anddiameters. The unconstrained diameter (D, in FIG. 1) of the diastolicrecoil device may be about 40 mm to about 100 mm, and the height of thedevice when expanded (H, in FIG. 1) may range from about 10 mm to about60 mm, and when collapsed, the diastolic recoil device of any size willfit within a catheter of less than 12 mm for delivery. In someembodiments, the unconstrained diameter of the diastolic recoil deviceis chosen to be oversized in relationship to the diameter of theventricle that it is installed within. In one embodiment, a singlestrand extends around essentially the entire periphery of the membraneso that the flexible periphery of the membrane between each pair of ribsis effectively sealed against the heart wall. The hub may have adistally extending stem with a non-traumatic support component. Thedistally extending stem with non-traumatic support component togethermay extend a variable distance from the base of the hub. The stem mayextend from about 2 mm to 20 mm from the hub to space the central hub aselected distance from the wall of the ventricle where the diastolicrecoil device is seated. In some embodiments, the stem distance can bevaried while retaining the same diameter membrane, thus permittingvariable partitioning of the volume of the chamber. In some embodimentsthe support component has a plurality of pods or feet, e.g., at leastthree, or any number desired to distribute the force of the diastolicrecoil device about a region of the ventricular wall surface tominimize, and preferably avoid immediate or long term damage to thetissue of the heart wall, by partitioning necrotic tissue such as tissueof a myocardial infarct (MI), or supporting weakened cardiac wall, andthe like.

In another aspect of the invention, a diastolic recoil device adaptedfor percutaneous delivery to a ventricle of a heart of a patientcomprising a plurality of radially expandable ribs connected at theirdistal ends to a central hub, is implanted in the ventricle of thepatient wherein the radially expandable ribs are adapted to provideelastic support between opposing ventricular walls.

In an embodiment of the invention, a diastolic recoil device adapted forpercutaneous delivery to a ventricle of a heart of a patient comprisinga plurality of radially expandable ribs coupled at their distal ends toa central hub is implanted in the ventricle, wherein the ribs areadapted to augment ventricular wall movement during diastole.

In yet another embodiment of the invention, a diastolic recoil deviceadapted for percutaneous delivery to a ventricle of a heart of a patientcomprising a plurality of radially expandable resilient ribs connectedat their distal ends to a central hub and one or more anchor elements ateach of the proximal ends of the ribs are adapted to secure the deviceto a selected area of a wall within the ventricle, wherein the ribs areadapted to support the wall and unload the cardiomyocytes to limitremodeling of the heart.

In another embodiment of the invention, a diastolic recoil deviceadapted for percutaneous delivery to a ventricle of a heart of a patientcomprising a plurality of radially expandable ribs connected at theirdistal ends to a central hub is implanted in a patient, wherein the ribsare adapted to reduce diastolic pressure of a ventricle of the heartonce deployed.

In still another embodiment, a diastolic recoil device adapted forpercutaneous delivery to a heart of a patient comprising a plurality ofradially expandable ribs connected at their distal ends to a centralhub; and a plurality of anchor elements attached to a plurality of saidribs at their proximal ends wherein the anchor elements are adapted tosecure the apparatus to a wall of a ventricle of said heart; and,wherein once the device is implanted in a ventricle of a patient, thedevice is adapted to reduce a volume of the ventricle to improve thepressure-volume relationship of the ventricle.

In another embodiment, a diastolic recoil device comprising aresiliently deformable member and a plurality of anchors, is deliveredpercutaneously to and anchored within the interior of a ventricle of apatient's heart to span a region of said ventricle, wherein theresiliently deformable member deforms from a first shape to a secondshape during systole and to return to the first shape during diastole toassist in expansion of the ventricle.

In other embodiments, a diastolic recoil device comprising a resilientlydeformable member and a plurality of anchors, is deliveredpercutaneously to and anchored within the interior of a ventricle of apatient's heart to span a region of the ventricle, where the resilientlydeformable member stores energy during systole and releases storedenergy back to a wall of the ventricle in synchrony with a heart cycle.

In some embodiments, a diastolic recoil device further comprises adelayed release spring having either a damped expansion mode or atriggered release such that the release of recoil forces back to thewalls of the ventricular chamber can be selectively timed duringdiastole. This may aid individuals who require additional force to beapplied back to ventricular walls during differing portions of diastole.

In yet another embodiment of the invention, a patient may be treated whohas no systolic dysfunction, but does have diastolic dysfunction.Devices and methods are provided which utilize a diastolic recoil devicehaving a frame and a hub which can provide force back to the walls ofthe ventricle. However, the device does not have a membrane aspartitioning a portion of the ventricle may not be necessary for thesepatients. The frame may need differing characteristics to perform, asthese patients may require more force to be applied to potentiallystiffened and thickened heart walls. Therefore the number of ribs may beincreased, the thickness of the ribs may be increased, the stiffness ofthe ribs may be increased, or the type of alloys or composite of whichthe frame is made may be different from other devices provided for inthis invention. In this embodiment, the device may be seated lower thanthe base of the papillary muscles in the ventricle. The unconstraineddiameter of such a device may be at least about 25 mm to about 90 mm.

In another aspect of the invention, methods are provided which includepartitioning a chamber (e.g., left and/or right ventricles) of apatient's heart, exhibiting diastolic dysfunction disorder, or one whichexhibits the characteristics of diastolic dysfunction, into a functionalportion and an excluded, nonfunctional portion by implanting a diastolicrecoil device according to the present invention.

Some embodiments of the invention includes the use of a diastolic recoildevice having a partitioning membrane, preferably a reinforcedpartitioning membrane, with a pressure receiving surface, preferablyconcave, which defines in part the functional portion of the partitionedheart chamber when implanted or anchored within the patient's heart, inparticular, within the ventricle.

In other embodiments of the invention a patient suffering from a heartcondition is treated by advancing percutaneously a collapsed diastolicrecoil device comprising a plurality of radially expandable ribsconnected at their distal ends to a central hub and having an anchorelement at the proximal end of each of the ribs; expanding the ribs in aventricle of the heart; and, securing the device to a selected area of awall of the ventricle with the anchor elements thereby providing elasticsupport between opposing ventricular walls. The ribs thus absorbing andreleasing recoil forces back to the area of attachment reduce forcesdirected at the area of the heart in the newly created nonfunctionalportion of the ventricle. This reduction eases pressure on a weakenedarea of a cardiac wall of the nonfunctional portion of the chamber.

The storing and release of energy by the frame occurs in synchrony withthe action of the heart. This transfer of energy may decrease theventricular pressure in diastole, increase the atrio-ventricularpressure gradient, increase filling, and thus improve ejection fractionDyskinetic or aneurystic ventricular walls result in dyssynchronousbehavior during the cardiac cycle, leading to inefficient pumpingfunction. Installation of a device of the invention can remove thosedyssynchronous contributions to heart rhythms, restoring overallsynchrony in the cardiac cycle, and thus improve ejection fraction.

In yet another embodiment of the method a patient suffering from a heartcondition is treated by advancing percutaneously a collapsed diastolicrecoil device comprising a plurality of radially expandable ribsconnected at their distal ends to a central hub and having an anchorelement at the proximal end of each of the ribs; expanding the ribs in aventricle of the heart; and, securing the device to a selected area of awall of the chamber with the anchor elements thereby augmenting aventricular wall movement during diastole.

Another embodiment of the method treats a patient suffering from a heartcondition by advancing percutaneously a collapsed diastolic recoildevice with a plurality of radially expandable resilient ribs connectedat their distal ends to a central hub, and an anchor element at theproximal end of each of the ribs; expanding the ribs in a ventricle ofthe heart; and, securing the device to a selected area of a wall of theventricle with the anchor elements wherein the ribs support theventricular wall, unloading the myocardium, decreasing stress and thusbenefiting mechanical function. More efficient function and decreasedstress leads to decreased rates of dilation, and hence may limitremodeling of the heart.

Still another method of the invention treats a heart of a patient byadvancing percutaneously a collapsed diastolic recoil device comprisinga plurality of radially expandable ribs connected at their distal endsto a central hub and having an anchor element at the proximal end ofeach of the ribs into a ventricle of the heart; expanding the ribs inthe chamber of the heart; and, securing the device to a selected area ofchamber wall with the anchor elements thereby reducing the diastolicpressure of the ventricle.

In another aspect of the invention methods are provided to reduce mitralvalve regurgitation by advancing percutaneously a collapsed diastolicrecoil device comprising a plurality of radially expandable ribsconnected at their distal ends to a central hub and having an anchorelement at the proximal end of each of the ribs; expanding the ribs in aventricle of the heart; and, securing the device to a selected area of awall of the ventricle with the anchor elements thereby reducing mitralvalve regurgitation.

Another embodiment of the invention is a method of treating a patientsuffering from a heart condition by advancing percutaneously to theinterior of a ventricle of the patient's heart a diastolic recoil devicecomprising a resiliently deformable member and a plurality of anchors;securing the device to opposing wall sections of the ventricle with theanchors; deforming the deformable member as the opposing wall sectionsmove toward each other during systole; and providing a recoil force fromthe deformable member to the wall sections during diastole.

Yet another embodiment is a method of treating a patient suffering froma heart condition by advancing percutaneously to the interior of aventricle of the patient's heart a diastolic recoil device comprising aresiliently deformable member and a plurality of anchors; securing thediastolic recoil device to opposing wall sections of the ventricle withthe anchors; storing energy within the deformable member as the opposingwall sections move toward each other during systole; and releasingenergy from the deformable member to the wall sections during diastole.

In some embodiments of the invention, use of the diastolic recoil deviceor the methods of treatment results in improvement in the ejectionfraction of the ventricle. The ejection fraction increase may be atleast about 5% up to about 90%.

In some embodiments of the invention, use of the diastolic recoil deviceor the methods of treatment results in decreasing the left ventricle(LV) functional chamber by about 10% to 40%.

In some embodiments of the invention, use of the diastolic recoil deviceor the methods of treatment results in decreasing minimum LV pressureduring diastole at least by about 5%.

In some embodiments of the invention, use of the diastolic recoil deviceor the methods of treatment results in decreasing end-diastolic pressureby at least about 5%.

The diastolic recoil device may be installed according to the methods ofthe invention in about one hour. The implantation of the deviceaccording to the methods of the invention requires require periods ofabout 25 minutes under a fluoroscope to install the partitioning device.

Similarly suitable diastolic recoil devices and methods may be used inthe left or right ventricle or other heart chambers.

In some embodiments of the invention, after implantation of a diastolicrecoil device of the invention, the left ventricle end systolic volumeindex (LVESVI) of the patient is decreased at least by about 5%.

In other embodiments of the invention, a number of biochemical markersare measured to evaluate cardiac function. One of these, NT-Pro-BrainNatriuretic Peptide (NT-Pro-BNP), is a regulatory peptide which isproduced in the ventricle, and is related to the level of stress inmyocardium. NT-Pro-BNP is decreased post-implant by at least about 10%.

In some embodiments of the invention, implantation of a partitioningdevice reverses the decline in ventricular function which may mitigatemitral valve regurgitation and/or decrease the stress on impaired valveleaflets sufficiently to alleviate regurgitation. Diastolic recoildevice implantation according to this invention may therefore benefitpatients with mitral valve regurgitation from any cause and decreasesthe regurgitant fraction by at least about 10%.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevational view of a partitioning device embodyingfeatures of the invention in an expanded configuration.

FIG. 2 is a plan view of the diastolic recoil device shown in FIG. 1illustrating the upper surface of the device.

FIG. 3 is a bottom view of a diastolic recoil device.

FIG. 4 is a perspective view of one embodiment of a non-traumatic tip ofthe distally extending stem of a diastolic recoil device.

FIG. 5 is an elevational view of a diastolic recoil device embodying analternative support component of the invention in an expandedconfiguration.

FIG. 6 is a partial elevational view of a diastolic recoil deviceembodying an alternative support component with curved bumper shapedfeet.

FIG. 7 is a partial elevational view of a diastolic recoil deviceembodying an alternative support component with J-shaped feet.

FIG. 8 is a partial elevational view of a diastolic recoil deviceembodying an alternative support component with J-shaped feet.

FIG. 9 is a partial elevational view of a diastolic recoil deviceembodying an alternative support component with J-shaped feet.

FIG. 10 is a partial cross-sectional view of a lower section of adiastolic recoil device as shown in FIG. 2 taken along the lines212-212, showing details of connection of the ribs to the hub, thesupport component, and feet of a diastolic recoil device.

FIG. 11 is a detail cross sectional view of the hub of a diastolicrecoil device as shown in FIG. 10, taken along lines 1013-1013.

FIG. 12 is a plan view of a diastolic recoil device incorporating adelayed or damped spring release mechanism attached to the pressurebearing side of the frame of the device.

FIG. 13 is a plan view of a diastolic recoil device which includes aframe and a hub but no membrane.

FIG. 14 is an elevational view of the device shown in FIG. 13.

FIG. 15A is a partial elevational view of an alternate basal support forthe device shown in FIGS. 13 and 14.

FIG. 15B is a partial elevational view of an alternate basal support fordevice shown in FIGS. 13 and 14.

FIG. 16A is a schematic view of a patient's heart exhibitingcharacteristics of heart failure or incipient CHF.

FIG. 16B is a schematic view of the patient's heart of FIG. 16A aftertreatment according to a method of the present invention using a roundshaped diastolic recoil device.

FIG. 17 is a schematic view of the patient's heart of FIG. 16A aftertreatment according to a method of the present invention using anelliptical shaped diastolic recoil device.

FIG. 18A is a drawing of the echocardiograph image of the patient'sheart after treatment according to a method of the present inventionusing a diastolic recoil device at end-diastole, highlighting theeffective diameter of the diastolic recoil device in the relaxed state.

FIG. 18B is a drawing of the echocardiograph image of the patient'sheart after treatment according to a method of the present inventionusing a diastolic recoil device at end-systole, highlighting theeffective diameter of the diastolic recoil device in the constrainedstate.

FIG. 19 is a diagrammatical illustration of the elastic characteristicsof an embodiment of a diastolic recoil device implant.

FIG. 20 is a schematic representation of a heart with a ventricle havingtwo distinct regions of myocardium with different contractileproperties, Region 1 and Region 2.

FIGS. 21A-C are diagrammatical representations of the end-systolicpressure volume relationship (ESPVR) and end-diastolic pressure volumerelationship (EDPVR) of the ventricle of FIG. 20 prior to installationof a partitioning device.

FIG. 22 is a schematic representation of a heart with a ventricle havingtwo distinct regions after installation of a diastolic recoil device.

FIGS. 23A-C are diagrammatical representations of the ESPVR and EDPVR ofthe ventricle of FIG. 22 after treatment according to the presentinvention, and shows the comparison of the Stroke Volume,pre-implantation and post-implantation.

FIG. 24A is a diagrammatical illustration of the left ventricularpressure (LVP) in one dilated ventricle with diastolic dysfunction.

FIG. 24B is one diagrammatical illustration of the left ventricularpressure (LVP) of the ventricle of FIG. 4A after treatment according tothe present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is directed to devices and methods for thetreatment of a patient's organ such as a heart. In some cases the heartis susceptible to or experiencing diastolic dysfunction, mitral valveregurgitation or heart failure.

Diastole is the phase of cardiac cycle during which relaxation of theheart muscles occurs after ejecting blood into general circulation andis governed by active and passive properties of the myocardium,geometrical characteristics of the chamber and external forces.

In the cardiac cycle left ventricular diastolic filling begins withopening of the mitral valve as pressure in the ventricle falls belowpressure in the atrium. As the ventricle begins to contract the pressurein the ventricle soon exceeds that of the atrium and the mitral valvecloses, which marks the end of diastole. The ventricular pressure andvolume at this point are referred to as end-diastolic pressure (“EDP”)and end-diastolic volume (“EDV”), and the beginning of ventricularsystole.

The rate and amount of left ventricular diastolic filling depends uponthe positive pressure upstream of the left ventricle provided by venousreturn and decreasing pressure provided within the left ventricle byexpansion of the ventricle during diastole. A reduction in ventricularcompliance (i.e., increase in stiffness of ventricular heart wall) mayresult in less diastolic expansion of the ventricle, less ventricularfilling (i.e. decreased end-diastolic volume EDV) and a greaterdiastolic pressure, resulting in a change in the ventricular diastolicpressure-volume characteristics. In a case of ventricular enlargementand/or the decrease of myocardial function, the left ventricular elasticrecoil forces may be diminished, therefore leading to increase of theventricular filling pressure.

Diastolic dysfunction may also be caused by changes in the rate anddegree of left ventricular relaxation, which as stated above, in part isan active process. Several factors can affect left ventricularrelaxation, including inotropic stimulation, fast heart rates,non-uniform heart activation and altered timing of all the forces thatoppose ventricular ejection. Since calcium uptake by the sarcoplasmicreticulum is energy-dependent, any process that decreases theavailability of high-energy phosphates, such as ischemia or hypoxia,also impairs myocardial relaxation.

Diastolic dysfunction is established, for example, by measurements ofvarious echocardiographic parameters such as decreased peak fillingvelocity and prolonged relaxation time, signs of increased fillingpressure and clinical symptoms of dyspnea and peripheral edema.

The devices and methods herein can be used to treat a patient's heartsuffering from a diastolic dysfunction disorder or a conditionexhibiting the characteristics of diastolic dysfunction. The devices andmethods herein involve implanting within the ventricle a device whoseshape elastically distorts during systole and recoils during diastole toaugment the ventricle's natural recoil action. In one embodiment, thedevice also partitions the patient's ventricle into a functional portionand an excluded, non-functional portion. The method may be used to treata heart, in particular the left ventricle, which is exhibiting signs ofdiastolic dysfunction. Diastolic dysfunction may evidence itself byportions of the chamber becoming dilated, dyskinetic or akinetic,depending on the particular pathology inducing damage to the heart.

A. Device

FIG. 1 illustrates a diastolic recoil device 130 which embodies featuresof the invention and which may be utilized in practicing the methodsherein. The device 130 includes hub 132, preferably centrally located onthe diastolic recoil device, and a radially expandable reinforcing frame133 formed of a plurality of ribs 134 connected at their distal end tothe hub. Alternative embodiments of the devices herein include at leastthree ribs. The ribs form an elastic frame and can be made of materialsuch as, for example, Nitinol stainless steel, titanium alloys, NiTialloy, other metal alloys, or plastic composites. In some cases, theribs/frame are made of a material which allows for compression of thefree proximal ends towards the central axis during delivery and selfexpansion upon deployment (e.g. in the patient's heart). The ribs 134have distal ends 136 which may be pivotally mounted to the hub 132 andbiased outwardly or fixed to the hub, and free proximal ends 137 whichare configured to curve or flare away from a center line axis 138 atleast upon expansion of the diastolic recoil device.

Proximal ends 137 of ribs 134 in their expanded configuration angleoutwardly from the hub at an angle θ of about 20-90° away from acenterline axis 138 of the device. The free proximal ends 137 curveoutwardly so that the membrane when secured to the ribs of the expandedframe forms a trumpet-shaped concave pressure receiving surface.

Proximal ends 137 of ribs 134 can include anchors 150 configured toengage, and preferably penetrate into, the target tissue (e.g.endocardium of heart chamber to be partitioned, i.e. a ventricle). Thisenables the securing of a peripheral edge of the diastolic recoil deviceto the heart wall and fixation of the diastolic recoil device within thechamber so as to partition the chamber into two portions. Anchors 150are configured to penetrate the tissue lining at an angle ranging from30-120 degrees to the centerline axis 138 of the partitioning device.Anchors 150 can include barbs, hooks and the like which preventundesired withdrawal of device 130 from the target tissue.

A membrane 131 can be attached to the ribs 134 of the frame. Membrane131 can be made of a porous material, for example, expandedpolytetrafluoroethylene (ePTFE, or GORE-TEX®, one commercially availableproduct) or a non-porous material. When membrane 131 is porous, itfacilitates tissue ingrowth after deployment in the non-functionalportion of the heart chamber. Membrane 131 can also be formed from othermesh materials including metals, alloys, or composites. In some casesMembrane 131 is formed from a biocompatible polymeric material such asnylon, polyethylene terephthalate (PET) or polyesters such as hytrel.While not shown in detail, the membrane 131 has a first layer secured tothe concave face of the frame formed by the ribs 134, which creates apressure receiving surface 135. When the diastolic recoil device 130 isdeployed upon implantation, the pressure receiving surface 135 ispresented to the functional portion of the partitioned chamber. Themembrane 131 may have a second layer secured to the convex face of theframe formed by the ribs 134, creating a non-pressure receiving surface145. When the diastolic recoil device 130 is deployed, the non-pressurereceiving surface 145 is presented to the non-functional portion of thepartitioned chamber. The manner of application of the layers of membraneto the ribs is described in co-pending application Ser. No. 10/913,608,filed on Aug. 5, 2004, entitled “Ventricular Partitioning Device”,assigned to the assignee of the present invention, and incorporatedherein by reference in its entirety.

The hub 132 shown in FIG. 1 preferably has a distally extending stem 143with a non-traumatic support component 144. The distally extending stem143 with non-traumatic support component 144 together may extend avariable distance from the base of the hub 132, in order to space thedevice a selected distance from the wall of the chamber where the deviceis to be seated, thus permitting variable partitioning of the volume ofthe chamber. The stem 143 and support component 144 together may extendfrom about 3 mm to about 15 mm from the central hub 132 to isolatediffering proportions of the chamber or to provide suitable fits fordiffering size hearts.

Diastolic recoil devices according to the present invention have severaldistinct configurations. The unconstrained configuration is measuredprior to any constriction or installation within a patient, andrepresents the largest diameter possible. For example, the diameter (D)as shown in FIG. 1 of a device in its unconstrained configuration is atleast 35 mm, up to about 100 mm, and its height (H) is at least 10 mm,to about 60 mm, as needed to fit within the heart of a patient as morefully discussed below. When in its collapsed configuration, a diastolicrecoil device has a diameter of less than 12 mm, such that it fits in acatheter for endovascular delivery. Once a diastolic recoil device hasbeen implanted into a chamber of the heart, the flexible and resilientnature of the frame yields two further configurations. The largestinstalled configuration occurs at the end of diastole, and is referredto as End Diastole Diameter (EDD). The smallest installed configurationoccurs at the end of systole, when the chamber is compressed to itssmallest size, and this diameter is referred to as the End SystoleDiameter (ESD).

Prior to the implantation procedure (as described further below), thediastolic recoil device implant is matched to the size of the leftventricle (e.g., the chamber into which it will be implanted) bycomparing the left ventricle end-diastolic diameter at the level of thebase of the papillary muscles (“landing zone” diameter) to theunconstrained diastolic recoil device diameter. In order to maximize theoccurrence of a permanent seal between the implant and the endocardium,the unconstrained diameter of the selected diastolic recoil device isoversized as compared to the diameter of the landing zone.

Implantation of the oversized diastolic recoil device results in storingcompressive forces in the elastic NiTi frame of the device. The originof compressive forces is a bending deformation of the resilient frameribs. The decrease of the unconstrained frame diameter to the landingzone diameter is associated with a radial tip displacement of each framerib while the opposite end of the rib is fixed to the hub of the frame,therefore causing a flexing deformation of the ribs and a reboundingforce attempting to return the frame to the unconstrained diameter.These outward recoil forces are transmitted to the myocardium viaproximal ends of the ribs implanted into the myocardium, thus applyingpressure against the wall of the ventricle. In some embodiments, theunconstrained diameter of the diastolic recoil device is selected to beoversized by at least about 10% up to about 60% over the diameter of thelanding zone. The diastolic recoil device is elastic and itsconfiguration changes from a small diameter at end-systole (ESD) to alarger diameter (EDD) at end-diastole. The compression of the diastolicrecoil device from end-diastolic to end-systolic configuration causesadditional compressive forces to be stored in the elastic frame of thedevice and is preferably designed to be substantially equivalent at endsystole to the elastic restoring forces that originate in the myocardiumin a healthy heart. Thus the amounts of outward recoil forces that aretransmitted to the walls of the ventricle during diastolic filling areenhanced and augment outward motion of the ventricular walls. Theexpansion of the ventricle is assisted by the expansion of the ribs toimprove diastolic function of the ventricle. Resultantly, stress isdecreased in the myocardium, which is beneficial for more efficientmechanical function. As stress is a major cause of dilation,implantation of a device and its contribution of recoil forces back tothe heart wall may limit remodeling in the ventricle.

FIG. 2 illustrates a top view of a diastolic recoil device 230 in itsunconstrained configuration, as viewed from above the pressure receivingsurface 235. The diastolic recoil device 230 of FIG. 2 has ribs 234which are radially expandable and connected at their distal end to acentral hub. The ribs are adapted to provide an elastic recoil force toa wall of a chamber of a heart (e.g. a left or right ventricle). Theribs store energy during systole and release the stored energy back tothe wall of the chamber of the heart in synchrony with the heart cycle.The device 230 further comprises a membrane 231 coupled to the radiallyexpandable ribs 234. At least part of membrane 231 is secured to apressure receiving side of the frame 233, creating the pressurereceiving surface 235. Radial expansion of the free proximal ends 237unfurls the membrane 231 secured to the frame 233 so that the membranepresents the pressure receiving surface 235 which defines the functionaland nonfunctional portions of the chamber. A peripheral edge 239 of themembrane 231 may be serrated as shown in FIG. 2. A serrated edge ofperipheral edge 239 in this embodiment helps the membrane spread flat atthe periphery. Anchors 250 can include barbs, hooks and the like whichprevent undesired withdrawal of device 130 from the wall of the chamberof heart after implantation of the device 230.

The ribs 234 may be individually of variable length and the membrane 231may be of variable shape suitable to practice the present invention. Insome embodiments the membrane 231 and frame 233 define a circularperiphery and in other embodiments the membrane 231 and frame 233 definean eccentric or elliptical periphery.

In one embodiment, a strand 240 extends around essentially the entireperiphery of the membrane so that the flexible periphery of the membranebetween each pair of ribs 234 is effectively sealed against the heartwall. The effectiveness of the seal contributes to facileendothelialization of the pressure receiving surface of a porousmembrane. Once endothelialized, the membrane supports regrowth of a newinner wall of the chamber. The expansive strand 240 is formed frommaterial which is stiffer than the flexible, unsupported material of themembrane to provide an outward expansive force or thrust to preventformation of undesirable inwardly directed folds or wrinkles when theribs of the diastolic recoil device are in a contracted configuration. Asuitable strand 240 is formed from materials such as polypropylenesuture or super-elastic NiTi alloy wires. Such strands are typicallyabout 0.005 to about 0.03 inch (about 0.13 to about 0.76 mm) in diameterto provide the requisite outward expansive force when placed in acircular position such as around the periphery of the membrane in lessthan completely expanded configuration. Ends 241 and 242 of theexpansive strand 240 are shown extending away from the diastolic recoildevice in FIG. 2. The ends 241 and 242 may be left unattached or may besecured together, e.g. by a suitable adhesive, or to the membrane 231itself. When the diastolic recoil device is in the collapsedconfiguration for delivery, the outwardly biased strand 240 ensures thatthere are no inwardly directed folds or wrinkles and that none areformed when the device is expanded for deployment within the heartchamber. The strand 240 may be several strands of materials as above,rather than just one.

FIG. 3 is a bottom view of a device 330 herein. The nonpressurereceiving surface 345 of the membrane 331 which is secured to the ribs334 (dotted lines) are illustrated in this view. Extending from the baseof the frame 333 are feet 355 which support the device within thenon-functional portion of the chamber being partitioned against a walltherein. Feet 355 extend radially and preferably are interconnected bylateral supports 346 which help distribute the force over an expandedarea of the surface of the chamber. Feet 355 and lateral supports 346are made of resilient material which can support the device withoutcausing trauma to the wall of the chamber at contact points. Thisminimizes or avoids immediate or long term damage to the tissue of theheart wall. The diastolic recoil device can be used to support weakenedtissue of damaged heart wall such as necrotic tissue caused bymyocardial infarction (MI) and the like.

FIG. 4 is a side view of the support component of the device. Thesupport component 444 has a plurality of feet 455, e.g., at least threeor any variable number. The support component 444 atraumaticallycontacts the wall of the ventricle within the nonfunctional portion ofthe partitioned ventricle, and distributes direct pressure on the wallto minimize stress on the cardiac wall in the nonfunctional portion ofthe partitioned ventricle through the feet 455. Support component 444comprises a stem coupled to a non-traumatic base structure such as theplurality of feet 455 and connected on its other extremity to the stem443 which extends distally from the non-pressure receiving side of theframe of the device. The support component 444 can vary in length fromabout 3 mm to about 12 mm such that the non functional portion issufficiently large in size/volume to partition necrotic tissue, such astissue of a myocardial infarct (MI), a weakened cardiac wall, or thelike. A web of material (not shown) may extend between adjacent feet 445to provide further support in addition to or in lieu of the supports446.

Alternative embodiments of the devices comprise feet as shown in FIGS.5-9. FIG. 5 illustrates a diastolic recoil device 530 comprising a frame533 with ribs 534. The membrane 531 is attached to the frame 533 and theanchors 537 contact the wall of the chamber to secure the device withinthe chamber in order to partition it. Device 530 has a nontraumaticsupport component 544 which has a simple rounded end which is connectedto the stem 543. The stem 543 is connected to the central hub 532 whichis connected to the frame 533. FIG. 6 illustrates an alternative supportcomponent 644 for the devices of the invention. Support component 644has a plurality of curved bumpers 645 which act as “feet” and contactthe wall of the chamber atraumatically. There may be a variable numberof curved bumpers to distribute the force that the support componentwill deliver to the wall of the chamber. FIG. 7 illustrates analternative support component 744 which has feet such as the pluralityof J-bumpers 745. FIG. 8 illustrates a different embodiment of thesupport component 844 which has a plurality of J-shaped bumpers 845.FIG. 9 illustrates another embodiment of the support component 944 whichhas a soft, non-traumatic coil 945 which contacts the wall of the heartchamber, and distributes the force from a diastolic recoil device to alarger area of the wall of the heart, reducing strain on weakened ornecrotic areas of the chamber.

As shown in FIG. 10 the distal ends 1036 of the ribs 1034 are securedwithin the hub 1032 and, as shown in the detail of FIG. 11, atransversely disposed connector bar 1047 is secured within the hub whichis configured to secure the hub 1032 and thus the diastolic recoildevice 1030 to a delivery system such as that described in co-pendingapplications referenced above. Ser. No. 10/913,608, filed on Aug. 5,2004, entitled “Ventricular Partitioning Device”, assigned to theassignee of the present invention, and incorporated herein by referencein its entirety. This connector bar permits selective connection of thediastolic recoil device to a delivery catheter for delivery within theventricle, selective placement of the device once within the ventricleto partition the ventricle, selective deployment of the partitioningdevice and selective release of the diastolic recoil device from thedelivery catheter. FIG. 10 also illustrates the connection betweenconnector hub 1032, stem 1043, support component 1044, and feet 1045.

Another embodiment of the invention is envisioned wherein the device isutilized to deliver the recoil energy not throughout the phase ofdiastolic filling, but at selected time intervals during filling. Adevice 1230 further incorporating a delayed release spring 1260 as shownschematically in FIG. 12, can be utilized to assist diastolic function.In the top view of device 1230, delayed response spring 1260 is attachedto restraint struts 1261 which in turn releasably contact the frame 1233on the non-pressure bearing side 1245 of the membrane 1231. Afterinstallation by anchoring device 1230 to the ventricle walls withanchors 1250, the majority of the recoil force stored in the device isnot freely releasable immediately at the end of systole. Instead, theventricle begins an unassisted expansion while the device is partiallysecured from freely expanding. At a predetermined point during diastolicexpansion, which may be customizable for each patient, the delayedrelease mechanism is triggered. The restraint struts are 1261 releasedfrom contact with the frame 1233, and the stored energy fully releasedat that point in the cardiac cycle. Thus, the majority of the recoilenergy can be given back to the ventricular wall at a select pointduring diastole, as required for a particular patient. Anotherembodiment of this aspect of the invention may have a spring meansincluding only a damped releasing mechanism. In these embodiments, thesubsequent contraction of the ventricle during systole re-engages thedelayed release spring mechanism or restores the damped spring torestore the contact between the restraint struts 1261 and the frame 1233when the frame is in the compressed state for further cycles of delayedrecoil assistance to the ventricle.

Yet another embodiment of the invention can be envisioned for a patientpopulation that has no systolic dysfunction but does have diastolicdysfunction. This population may not have dilation of the heart andpartitioning the ventricle to reduce the volume of the ventricle is inthis case not necessary. To gain more efficient diastolic filling, adevice as shown in FIG. 13 may be utilized, which has a frame 1333 andcentral hub 1332 as previously described, but which has no membrane. Theresilient frame provides force back to the walls of the ventricle andimproves the diastolic function of the heart. The frame may need to bedifferent from the frames of other embodiments of this invention, i.e.frame 133 of FIG. 1. In this application, the ventricles of thispopulation of patients may require more force to be applied back to theventricular walls, which may be thickened and stiffened relative tohealthy ventricular walls. It may also be necessary to increase thenumber of ribs, the thickness of the material of the ribs, the relativestiffness of the ribs, and/or use different alloys or materialcompositions to form the frame in order to manufacture a device withappropriate resiliency/stiffness properties. The device may seat lowerin the ventricular chamber, and may thus require devices with smallerdiameters relative to those used for patients with ventricular dilation.The size matching then is made for the end-diastolic diameter of alanding zone at a level further below the base of the papillary muscles.The unconstrained diameter of devices according to this embodiment ofthe invention may therefore be at least 25 mm up to about 90 mm. Thecentral hub 1432, as shown in the side elevation view of a devicedepicted in FIG. 14, may not have any distal extension and may ends as aflat disk. A distal extension of hub 1432 may consist of a short roundednub, or may connect to flexible basal supports which may stabilize thedevice in its seat in the apex of the ventricle. The basal supports maybe configured in many ways. Two examples are given in FIGS. 15A and 15Brespectively, shown as basal supports 1561A and 1561B.

Implantation of the devices herein can be accomplished endovascularly orintraoperatively in as little as one hour by a physician orappropriately trained personnel. Such implantation presents limited riskto the patient and requires the patient to be under a fluoroscope for aperiod of as little as 20 minutes.

Implantation of the diastolic recoil device in the ischemic and enlargedventricle may bring back the ability of the ventricle to store elasticenergy during systole and return this energy in the form of elasticrecoil forces during diastole. In an embodiment, this return of energyin the form of elastic recoil may contribute to the improvement of thediastolic function, i.e., decrease of the filling pressure and increasein the magnitude of the early filling in patients with ischemic and/ordilated cardiomyopathy. Thus the ejection fraction of the chamber isincreased by at least about a 5% change.

Suitable diastolic recoil device designs useful in the practice of themethods of the present invention have been described in co-pendingapplications, Ser. No. 11/151,164, filed Jun. 10, 2005, entitled“Peripheral Seal for a Ventricular Partitioning Device”; and Ser. No.11/199,963, filed Aug. 9, 2005, entitled “Method for Treating MyocardialRupture;” both of which are assigned to the assignee of the presentinvention, and incorporated herein by reference in their entirety.Diastolic recoil devices of the present invention are deliveredpercutaneously or intraoperatively. A suitable delivery device isdescribed in co-pending application Ser. No. 10/913,608, filed on Aug.5, 2004, entitled “Ventricular Partitioning Device”, assigned to theassignee of the present invention, the full disclosure of which isincorporated herein by reference.

The diastolic recoil devices may be conveniently formed by the methoddescribed in above-referenced co-pending application Ser. No. 10/913,608assigned to the assignee of the present invention and which isincorporated herein by reference in its entirety.

B. Uses of the Devices

FIG. 16A is a schematic illustration of a patient's heart 1610 showingthe right ventricle 1611 and the left ventricle 1612 with the mitralvalve 1613 and aortic valve 1614. A pericardium membrane 1615 is shownsurrounding the heart 1610. FIG. 16A illustrates a patient's heart withapical dilatation (round enlarged apex 1616 of the LV) which can befound in patients exhibiting characteristics of congestive heartfailure. FIG. 16B illustrates the left ventricle 1612 of FIG. 16A afterit has been partitioned, with a diastolic recoil device 1630 havingfeatures according to the present invention and as described furtherbelow, into a main functional or operational portion 1618 and asecondary, essentially non-functional portion 1617. FIG. 17 is aschematic view of the patient's heart of FIG. 16A after treatmentaccording to a method of the present invention using an ellipticalshaped diastolic recoil device 1730. The device 1730 is implanted intothe left ventricle 1712 of the heart 1710, creating a functional portion1718 and nonfunctional portion 1717.

FIGS. 18A and 18B are drawings of echocardiograph images of a patient'sheart at end-diastole, and end-systole, respectively. The contours ofthe diastolic recoil device implanted in the left ventricle are visibleas fine white lines in the base of the ventricle. Portions of the ribsand periphery can be seen in FIGS. 18A and 18B.

As can be seen from FIGS. 18A and 18B, the diameter of the elasticdiastolic recoil device is at its maximal implanted diameter (FIG. 18A)at end-diastole, and at its minimal implanted diameter at end-systole(FIG. 18B). End-systolic diameters (ESD) can be in the range from about25 mm to about 55 mm. End-diastolic diameters (EDD) can be in the rangeof about 45 mm to about 70 mm. The compression of the partitioningdevice from end-diastolic to end-systolic configuration causes elasticrecoil forces to be stored in the elastic frame of the device, and to betransmitted to the myocardium during ventricular filling in the outwarddirection thus enhancing outward motion of the ventricular walls. Thisstoring and release of energy by the frame occurs in synchrony with theaction of the heart. This transfer of energy may decrease theventricular pressure in diastole, increase the atrio-ventricularpressure gradient, increase filling, and thus improve ejection fractionDyskinetic or aneurystic ventricular walls result in dyssynchronousbehavior during the cardiac cycle, leading to inefficient pumpingfunction. Installation of a device of the invention can remove thosedyssynchronous contributions to heart rhythms, restoring overallsynchrony in the cardiac cycle, and thus improve ejection fraction. Inone embodiment of the invention the partitioning device is substantiallycircular but another embodiment of the invention utilizes an ellipticalshaped partitioning device as shown in FIG. 17. Other configurations ofthe partitioning device are compatible with the construction asdescribed above and with methods to partition a chamber of a heart asset forth here.

The devices herein can be used to treat a patient suffering from a heartcondition. Such heart conditions can include, for example, mitral valveregurgitation, myocardial infarction, or scar tissue or akinetic tissuein a heart chamber. A patient can be screened for treatment by the adevices herein by any means known in the art including, but not limitedto, measurements of echocardiographic parameters may be such asdecreased peak filling velocity and prolonged relaxation time, signs ofincreased filling pressure, clinical symptoms of dyspnea and peripheraledema, as well as low ejection fraction and a distance a patient canwalk in 6 minutes.

Prior to the implantation procedure (as described further below), thediastolic recoil device implant may be matched to the size of thechamber where it is to be inserted (e.g. left ventricle) when the deviceis to be inserted into the left ventricle this can be accomplished bycomparing the left ventricle end-diastolic diameter at the level of thepapillary muscles base. This diameter is referred to hereinafter as thelanding zone diameter. Measurement of landing zone diameter may be madeby any method known in the art including; echocardiography, fluoroscopy,PET, MRI, contrast angiography, and the like, the landing zone diameteris the compared to the relaxed deployed/device diameter. When a deviceis to be implanted in a ventricle, the ventricle may be dilated suchthat its end diastolic diameter is greater than 45 mm or even greaterthan 65 mm. In some cases, to maximize the occurrence of a permanentseal between the implant and the endocardium, the relaxed diameter ofthe selected diastolic recoil device is oversized as compared to thediameter of the landing zone. The relaxed diameter of the device can beoversized by at least about 10% and up to 60% over the landing zonediameter.

The diastolic recoil device implanted thus decreases the LV volume by atleast about 10% up to about 40%. The ratio of the nonfunctional portionto the functional portion, created by partitioning the ventricle by amethod of the invention is at least 1:10 or up to about 1:3.

The diastolic recoil device frame is elastic and its diameter changesfrom a small diameter at end-systole to a larger diameter atend-diastole. The compression of the diastolic recoil device fromend-diastolic to end-systolic configuration causes additionalcompressive forces to be stored in the elastic frame of the device, thusenhancing the ejection fraction of the chamber by at least about 10%, orup to about 90%.

The elastic characteristics of the diastolic recoil device implant maybe determined by a tensile/compression test, an example of which isdiagrammatically shown in FIG. 19. To conduct the test, the diastolicrecoil device is positioned inside a custom designed fixture which wasconnected to a force transducer. The fixture was designed to createsubstantially equal compressive radial force (compatible andcorresponding to physiological range of forces developed by normalmyocardial fibers) on all ribs 34 (as described below) of the implant,thus determining the compression stress-diameter relationship for theframe 33 (as described below) of the device. FIG. 19 shows an exemplaryelastic property of the diastolic recoil device. As can be noted fromthe figure, the magnitude of the elastic recoil forces stored in thediastolic recoil device implant increases as the diastolic recoil devicediameter decreases under compression.

It can further be noted that the stiffness of the implant increases in anon-linear fashion as the diameter of the implant decreases as it iscompressed to less than 50% of the diameter of the fully relaxedimplant.

Modeling experiments can be used to demonstrate the effect of implantinga diastolic recoil device of the invention. FIG. 20 is a schematicrepresentation of a heart with dilation and poor function in the leftventricle, having two distinct regions of myocardium surrounding theinterior of the ventricle. Region 1 represents normal myocardium andregion 2 represents dilated and dyskinetic or akinetic/myocardium. Asimulation experiment is performed, using an elastance model, asdescribed in J H. Artip; et al.; J. Thoracic and Cardiovascular Surg.,122(4), 775-782, 2001. The myocardial properties differ from one regionto the next and the global ventricular properties are calculated by theinteraction between the two virtual chamber regions, each chamber regionhaving its own pressure volume characteristics. FIGS. 21A-C represent asimulation carried out using a ventricle as in FIG. 20 without apartitioning device. In FIGS. 21A and B, the dashed lines labeled ESPVR(End Systolic Pressure Volume Relationship) represent the maximalpressure that can be developed by that section of the ventricle at anygiven left ventricular volume. The dashed lines in FIGS. 21A and Blabeled EDPVR (End Diastolic Pressure Volume Relationship) represent thepassive filling phase for the respective regions of the un-partitionedventricle, demonstrating the change in volume without great change inpressure, for each simulated region. As can be seen for Region 1(normal), during systole the pressure changes rapidly relative to volumechanges, while during diastole volume changes more rapidly (passivefilling) relative to pressure changes. In contrast, in the akineticregion, Region 2, in FIG. 21B, there is no passive filling duringdiastole, hence the EDPVR is coincident with the ESPVR. Of note is theslope of the ESPVR in Region 2 (FIG. 21B), which is greater than that inRegion 1 (FIG. 21A), as the slope is the reciprocal of ventricularcompliance. Hence, akinetic Region 2 demonstrates greatly reducedventricular compliance. The end-systolic pressure-volume relationship(ESPVR) and end-diastolic pressure-volume relationship (EDPVR) for theventricle of FIG. 20 was determined by the sum (FIG. 21C) of the virtualvolumes of the Regions 1 (FIG. 21A) and 2 (FIG. 21B) at each pressure,as shown by the solid lines drawn in FIG. 21C.

In the second part of the simulation experiment, the effect is modeledwherein the akinetic Region 2 of a ventricle with diastolic dysfunction(as shown in FIG. 22) of the LV is partitioned by a partitioning deviceof the invention. The ESPVR and EDPVR for the individual contributionsfrom normal Region 1, the diastolic recoil device, and akinetic Region 2are represented in FIGS. 23 A and B. The normal Region 1 now exhibits asteeper slope to its ESPVR as the diastolic recoil device isolatesRegion 2 from Region 1, reducing the overall volume and conferringgreater resistance as systole proceeds. The solid line shown in FIG. 23Bshows similar information as that in FIG. 19, as it represents theperformance of the diastolic recoil device as it is compressed, and thedashed line in FIG. 23B is the ESPVR/EDPVR curve for the akinetic Region2 in FIG. 22. The new ESPVR and EDPVR for the ventricle as a whole areshown in FIG. 23C, as solid lines. The corresponding ESPVR and EDPVR forthe pre-implant ventricle from FIG. 21C are also reproduced in FIG. 23Cas dashed lines for comparison. As can be seen in FIG. 23C, the ESPVRand EDPVR curves of the post-implant ventricle (solid lines) are shiftedleftwards as compared to the curves of the dilated pre-implant ventricle(FIG. 23C “ESPVR Pre-Implant” and “EDPVR Pre-Implant”, dashed lines).However, the ESPVR curve for the partitioned ventricle is shifted morethan the EDPVR curve for the partitioned ventricle. This results inincreased pump function of the ventricle which can be demonstrated byexamining the resultant the pressure-volume loops. The stroke volume(SV) for the ventricle, pre-partitioned (FIG. 20) and partitioned (FIG.22), are indicated by the shaded volumes labeled “SV Pre-Implant” and“SV Implant”. The stroke volume is represented by the width of theseshaded volumes as filling proceeds along the EDVPR curves. Theright-hand boundary of the stroke volume is the pressure/volume line atend diastole, when isovolumetric contraction begins, and the left-handboundary is the volume/pressure line representing isovolumetricrelaxation during the heart cycle. The partitioned ventricle exhibitsincreased stroke volume (SV) compared to the dilated, pre-implantventricle with akinetic Region 2 at comparable end-diastolic and aorticpressures (“SV Implant” vs. “SV Pre-Implant” in FIG. 23C).

FIGS. 24A and 24B, are diagrammatical illustrations of the recordings ofthe left ventricular pressure (LVP) in one dilated ventricle withdiastolic dysfunction before and after implantation of a diastolicrecoil device, respectively. In FIG. 24A, diastolic dysfunction resultsin inefficient filling of the ventricle at relatively high meandiastolic pressure in the ventricle. The akinetic ventricle can neithercompress nor expand as effectively as a normal ventricular chamber. Theresultant filling pressure at early diastole is therefore higher than ina healthy heart and early filling is decreased. During installation ofthe diastolic recoil device, the device is anchored to functionalportions of the ventricle wall, partitioning the akinetic(nonfunctional) portion of the chamber. This mode of attachment allowsthe elastic frame of the partitioning device to gain energy from theeffectively contracting portion of the ventricular wall, by compressingthe elastically resilient frame. As the ventricle relaxes and expands,the energy stored in the frame is released and imparts additional recoilforce back to the ventricle wall, which aids in the process of fillingthe ventricular chamber. As can be seen from FIGS. 24A and 24B,implantation of the diastolic recoil device resulted in decreasedminimum diastolic pressures. In this example the minimum LV pressure isdecreased by at least 50% (contrasted by points A and A′ in FIGS. 24Aand 24B respectively) and mean diastolic pressure at least by 10%. Thecontribution of the elastic energy from the frame assisting expansion ofthe walls of the ventricle was observed in early diastole, therebyaugmenting filling and normalizing diastolic pressure. Decreased meandiastolic pressure of the partitioned ventricle compared to that of thepre-implant ventricle indicates improved diastolic function (meandiastolic LVP of ca. 14 mm Hg in FIG. 24B vs. “mean diastolic LVP of ca.22 mm Hg in FIG. 24A). These results demonstrate that the diastolicrecoil device improves either or both the systolic and diastolic LVfunction in the remodeled LV with a dysfunctional myocardial region.

The use of a diastolic recoil device and methods of the invention yieldsa decrease of minimum LV pressure during diastole by at least about 5%up to about 100%. The use of a diastolic recoil device by the methods ofthe invention yields a decrease of end-diastolic pressure by at leastabout 5%, and up to about 35%.

Other indicators of LV function may be measured upon installation of thediastolic recoil device. Some of these indicators are hemodynamicmeasurements, such as, for example, left ventricle end systolic volumeindex (LVESVI). LVESVI indicates the size of the ventricle at endsystole with values normalized to body size. The baseline value for ahealthy individual is ˜25 ml/m². LVESVI has significant predictive valuefor survival outcome, and may represent the most significant correlationused in diagnosis and treatment. In some cases, a patient can be firstdiagnosed as having heart disease by determining or detecting in thatpatient a LVESVI greater than 60 ml/m². Such patient is thus treated byimplanting one or more of the devices herein. The diastolic recoildevice, by partitioning the ventricle into functional and non-functionalportions, causes an initial decrease in LVESVI upon installation. Theimplantation of the diastolic recoil device may also promote positiveremodeling of the ventricle to further decrease ventricle volume as thesupported cardiac muscle more effectively contracts and expands, thusdecreasing LVESVI by at least 5%.

Left ventricle ejection fraction (LVEF), another hemodynamicmeasurement, is the percentage of the end diastolic blood volumeexpelled from the ventricle upon each cardiac cycle. LVEF of 60% orgreater are seen in healthy individuals, while an LVEF of 40% isconsidered the threshold value for diagnosis of heart failure withsystolic dysfunction. Implantation of the partitioning device increasesthe LVEF by at least about 5% and up to about 90%.

Other indices of ventricular function may also be used for diagnosis andfor therapeutic follow-up. A number of biochemical markers may bemeasured and used. One example is NT Pro-Brain Natriuretic Peptide, butmany other biological molecules, for example, neurohormones, proteases,and proteins related to distressed or abnormal function may be measuredto give quantification of the relative functionality of the ventricleprior and post-implant.

NT-Pro-Brain Natriuretic Peptide (NT-Pro-BNP) is a regulatory peptidethat is produced in the ventricle and has been shown to be related tothe level of stress in myocardium, as well as involved in adverseremodeling processes seen in late stage disease. A normal NT-BNP levelfor a healthy individual is generally in the range of 20-30 pg/ml, whilein an individual with end stage heart failure, a level can be as high as2000-3000 pg/ml, and in some instances there may be a correlationbetween BNP levels and LVEF. The use of NT-Pro-BNP levels as reliablemarkers for heart disease in a number of patient populations has beenproposed (J. L. Januzzi; Cleve. Clin. J. Med., 73(2), 149-52, 155-7,2006) and may offer advantages in ongoing patient monitoring and care.Thus the present invention contemplates treating a patient by firstdetermining the level of NT-Pro-BNP, and if the level of NT-Pro-BNP isgreater than 170 pg/ml (third quartile) or 450 pg/ml (fourth quartile),delivering to such patient one or more of the devices herein.Implantation of a diastolic recoil device improves cardiac function, anddecreases the level of NT-Pro-BNP observed post-implant by at leastabout 10%.

Mitral valve regurgitation can be observed in patients with diastolicdysfunction, and is coupled to poor outcome. Mitral valve regurgitationincreases in magnitude as the ventricle increases in size due topathological dilation. Intervention is often necessary as blood backflowinto the atrium leads to accelerated progression of heart failure.Standard therapies include both prescribed medications (i.e.vasodilators like ACE inhibitors and nitrates, and diuretics) andsurgical interventions to repair or replace mitral valves. However,these surgical interventions are invasive and may present high risk tothe patient. Diastolic recoil device implantation can reverse thedecline in ventricular function by decreasing the effective ventricularvolume which may obliterate or attenuate the cause of the mitral valveregurgitation. The severity of mitral valve regurgitation is categorizedby measuring the regurgitant fraction by, for example, echocardiography.Color Doppler flow on a transthoracic echocardiogram measures theforward flow through the mitral valve during ventricular diastole andcompares it to the outflow of blood through the aortic valve inventricular systole, permitting the calculation of the regurgitantfraction. The present invention contemplates treating a patient by firstdetermining the degree of mitral regurgitation as assessed by theregurgitant fraction and if the regurgitant fraction is at least 20%,delivering to such patient one or more of the devices herein. Diastolicrecoil device implantation may therefore benefit patients with mitralvalve regurgitation from any clinically relevant cause and decrease theregurgitant fraction by at least about 10%.

Although reference is made to a diastolic recoil device which isimplanted in the left ventricle, it is understood by those skilled inthe art that such reference is not limiting and similarly suitablediastolic recoil devices may be used in the right ventricle or otherheart chambers.

EXAMPLES Example 1

Symptomatic heart failure patients (New York Heart AssociationClassification levels II and III) diagnosed with ischemic cardiomyopathypost anterior infarction and systolic dysfunction were enrolled in astudy implanting a diastolic recoil device similar to the one shown inFIG. 1. Size selection of the specific device was based onechocardiography comparison with a mean landing zone diameter of 55.1 mm(mean diastolic value or largest value achieved during cardiac cycle).Either 75 mm (3/9 patients) or 85 mm (6/9 patients) diameter deviceswere installed in a 95.7 minute (mean value) procedure, requiring meanfluoroscope time of 25.5 minutes.

A number of hemodynamic and biochemical variables were examined in eachpatient before implant and at 90 day post implant and are represented inTable 1 below. Data is available for 4 patients at the 90 day timepoint.

TABLE 1 Exploratory Endpoints Baseline (n = 9) All data as mean valuesBefore Implant 90 days (n = 4) LVESVI (ml/m²) 101.8 72.7 LVEF (%) 29.337.2 Patients with MR 5/9 1/4 NT-Pro-BNP (pg/ml) 566 393

Left ventricle end systolic volume index (LVESVI) in a healthyindividual is usually around 25 ml/m². The mean baseline value for thepatient group is notably higher, at 101.8 ml/m². Significant reductionto 72.7 ml/m² (˜25%) for the LVESVI is observed at 90 days post implant.The ventricle has thus improved in function and was positivelyremodeled.

Left ventricle ejection fraction (LVEF) in a healthy individual isusually at least 60%. For this group the mean value observed beforeimplantation of the device was 29.3%, slightly less than half of thevalue seen for healthy patients. At 90 days post intervention anincrease in LVEF to 37.2% is observed which is an improvement of about27%. This is a significant improvement as the threshold value of LVEF todiagnose heart failure is often placed at 40%.

In the overall patient cohort, a significant proportion of the patients(5 of 9) experienced mitral valve regurgitation (MR) prior toimplantation. Of four patients who had experienced MR prior toimplantation and for whom data at 90 days post implantation isavailable, three patients had remission of symptoms, with only onepatient still experiencing MR. Thus, the improvement in LV functionprovided by implantation of a diastolic recoil device also providedreduction in MR regurgitation.

NT-Pro-brain Natriuretic peptide (NT-Pro-BNP) levels for a healthyindividual are estimated to be in the range of 20-30 pg/ml. In the groupof patients analyzed, the baseline mean value of NT-Pro-BNP prior toimplantation was 566 pg/ml. This was significantly decreased by the 90day timepoint to 363 pg/ml, an improvement of about 36%.

In Table 2 below represents data of overall functionality for theindividual patients. The 6 minute walk is a simple test which measuresthe distance a patient is able to traverse during a 6 minutes timedperiod. The mean distance the patient cohort traveled prior to implantwas 328 m. Ninety days post implant, data available for 4 patients showssignificant improvement (˜44%) to 471 m. The New York Heart Association(NYHA) Classification levels for the patients prior to implantation wereClass II/III for this group. At the 90 day timepoint, reassessment ofthe NYHA Classification was performed on the four patients withavailable data. Three of the four individuals could be reassigned toless severe disease classifications. Finally, the patients performed aself scoring questionnaire, the Minnesota Living with Heart Failure test(MLHF), and registered significant improvement in self assessment offunctionality. Thus, implantation of a diastolic recoil device of thisinvention demonstrated clear and self evident improvement in functionand quality of life for the patient group.

TABLE 2 Exploratory Endpoints Baseline (n = 9) Mean Values BeforeImplant 90 days (n = 4) 6 min walk (m) 328 471 Improvement in NYHA class— ¾ (75%) MLHF 22.9 12.7

While preferred embodiments of the present invention have been shown anddescribed herein, it will be obvious to those skilled in the art thatsuch embodiments are provided by way of example only. Numerousvariations, changes, and substitutions will now occur to those skilledin the art without departing from the invention. It should be understoodthat various alternatives to the embodiments of the invention describedherein may be employed in practicing the invention. It is intended thatthe following claims define the scope of the invention and that methodsand structures within the scope of these claims and their equivalents becovered thereby.

What is claimed is:
 1. A diastolic recoil device adapted forpercutaneous delivery to a heart of a patient comprising a plurality ofradially expandable ribs connected at their distal ends to a centralhub, and a membrane coupled to the ribs, wherein the ribs are adapted toanchor to a wall of a ventricle of the heart to compress and storeenergy during systole and to self-expand during diastole to provide anelastic recoil force to the wall of the ventricle.
 2. The device ofclaim 1, wherein the ribs are made of a resilient material to allowcompression and expansion.
 3. The device of claim 1, wherein the ribsare made of a NiTi alloy.
 4. The device of claim 1, wherein the ribs areconfigured to curve away from a center line axis of the hub at leastupon expansion of the recoil device.
 5. The device of claim 4, whereinthe ribs are configured to expand outwardly at an angle between about20° and about 90° away from the center line axis.
 6. The device of claim1, further comprising at least three ribs.
 7. The device of claim 1,further comprising anchoring elements on proximal ends of the ribs foranchoring the device to a selected area of the wall of the ventricle. 8.The device of claim 7, wherein the anchoring elements are spaced fromone another in an expanded configuration to allow for positioning of thedevice at a select angle relative to the ventricle.
 9. The device ofclaim 7, wherein the anchoring elements are configured to penetrate thewall to secure a peripheral edge of the device to the wall.
 10. Thedevice of claim 7, wherein the anchoring elements comprise a memberselected from the group consisting of barbs, hooks, and a combination ofthe same.
 11. The device of claim 7, wherein the anchoring elements areadapted to penetrate the wall at an angle between about 30° and about120° from a center line axis of the device.
 12. The device of claim 1,wherein the ribs are configured to curve away from a center line axis ofthe hub at least upon expansion of the recoil device to form atrumpet-shaped concave pressure receiving surface.
 13. The device ofclaim 1, further comprising a stem connected to and extending distallyfrom the central hub, wherein the stem is adapted to space the centralhub of the device a selected distance from the wall of the ventricle.14. The device of claim 1, further comprising a hollow connector memberextending proximally from the central hub along a central longitudinalaxis of the device wherein the connector member is adapted forreleasable connection to a delivery catheter.
 15. The device of claim14, wherein a distal end of the connector member includes feet adaptedto distribute force over an expanded surface of a wall of the ventricle.16. The device of claim 15, wherein the feet are interconnected bylateral supports.
 17. The device of claim 16, wherein the feet andlateral supports are made of resilient material to support the devicewithout causing trauma to the ventricle wall.
 18. The device of claim 1,further comprising a delayed release spring mechanism adapted to releasethe elastic recoil force back to the wall of the ventricle at a selectedpoint during diastole.
 19. The device of claim 1, wherein anunconstrained diameter of the device is oversized by at least about 10%up to about 60% over a landing zone diameter of the ventricle at enddiastole.
 20. The device of claim 1, wherein an unconstrained diameterof the device is about 25 mm to about 100 mm.
 21. The device of claim 1,further comprising a connector bar to permit selective deployment andrelease of the diastolic recoil device from a delivery catheter.
 22. Amethod of treating a patient suffering from a heart conditioncomprising: advancing percutaneously a collapsed diastolic recoil devicecomprising a plurality of expandable ribs connected at their distal endsto a central hub; self-expanding the ribs in a ventricle of the heart;securing the device to opposing walls of the ventricle thereby providingelastic support between the opposing ventricular walls; and storingenergy provided by the ventricle in the ribs during systole andproviding a delayed elastic recoil force to the opposing walls of theventricle from the ribs during diastole.
 23. The method of claim 22,further comprising selectively releasing the device from a deliverycatheter to cause the self-expanding.
 24. The method of claim 22,wherein storing energy provided by the ventricle in the ribs duringsystole and providing an elastic recoil force comprises providingelastic recoil force to the opposing walls of the ventricle from theribs at selected time intervals during filling of the ventricle.
 25. Themethod of claim 22 wherein storing energy provided by the ventricle inthe ribs during systole and providing an elastic recoil force comprisesproviding elastic recoil force during systole and delaying release of anelastic recoil force back to the walls of the ventricle until a selectedpoint after diastole begins.
 26. The method of claim 22, furthercomprising anchoring the device to a selected area of a wall of theventricle.
 27. The method of claim 22, further comprising penetrating atleast one of the opposing walls to secure a peripheral edge of thedevice to the at least one wall.
 28. The method of claim 22, furthercomprising partitioning the ventricle between a functional portion and anon-functional portion.
 29. The method of claim 28, further comprisingpermanently sealing the device in the ventricle.
 30. The method of claim28, wherein the portioning comprises decreasing left ventricular volumeby at least 10%.
 31. The method of claim 28, wherein the portioningcomprises decreasing minimum left ventricular pressure by at least about5%.
 32. The method of claim 22, further comprising improving ejectionfraction of the ventricle by at least about 10%.
 33. The method of claim22, further comprising improving a pressure-volume relationship of theventricle.
 34. The method of claim 22, further comprising assisting inexpansion of the ventricle.
 35. The method of claim 22, wherein thecollapsed diastolic recoil device further comprises an anchor element ata proximal end of each of the ribs, the method further comprisingsecuring the device to a selected area of a wall of the ventricle withthe anchor elements thereby augmenting a ventricular wall movementduring diastole.
 36. A method of treating a patient in need of moreefficient diastolic filling, the method comprising: advancingpercutaneously a collapsed diastolic recoil device comprising aplurality of expandable ribs connected at their distal ends to a centralhub and a stem connected to and extending distally from the central hub,wherein the stem is adapted to space the central hub of the device aselected distance from a wall of a ventricle, wherein the ribs arestiffened relative to healthy ventricular walls to augment ventriclewall movement during diastole; self-expanding the ribs in the ventricleof the heart; securing the device to opposing walls of the ventricle;and compressing the plurality of ribs during systole and providing acorresponding elastic recoil force to the opposing walls duringdiastole.
 37. A diastolic recoil device adapted for percutaneousdelivery to a ventricle of a heart of a patient comprising a pluralityof radially expandable ribs coupled at their distal ends to a centralhub, wherein the ribs are adapted to augment ventricle wall movementduring diastole, and to provide a recoil force to the ventricular wallsat a selected point during diastole that is delayed from the onset ofdiastole.
 38. A diastolic recoil device adapted for percutaneousdelivery to a heart of a patient comprising: a plurality of radiallyexpandable resilient ribs connected at their distal ends to a centralhub and one or more anchor elements at each of the proximal ends of theribs adapted to secure the device to a selected area of a wall within aventricle of the heart, wherein the ribs are adapted to support the walland decrease the stress in the wall thereby limiting remodeling of theheart, and a stem connected to and extending distally from the centralhub, wherein the stem is adapted to space the central hub of the devicea selected distance from the wall of the ventricle.
 39. A diastolicrecoil device adapted for percutaneous delivery to a heart of a patientcomprising a plurality of radially expandable ribs connected at theirdistal ends to a central hub and a membrane coupled to the ribs, whereinthe ribs are adapted to store energy and reduce diastolic pressure of aventricle of the heart when disposed in the ventricle.
 40. The device ofclaim 39, wherein the ribs are adapted to store the energy duringsystole and deliver a corresponding recoil force during diastole. 41.The device of claim 40, further comprising a spring mechanism to delaydelivery of the recoil force until a selected point after diastolebegins.
 42. A method of treating a heart of a patient comprising:advancing percutaneously a collapsed diastolic recoil device comprisinga plurality of radially expandable ribs connected at their distal endsto a central hub and having an anchor element at a proximal end of eachof the ribs and a membrane coupled to the expandable ribs; allowing theribs to self-expand in a ventricle of the heart; and securing the deviceto a selected area of a wall of the ventricle with the anchor elementsthereby reducing diastolic pressure of the ventricle of the heart.
 43. Adiastolic recoil device adapted for percutaneous delivery to a heart ofa patient comprising: a plurality of radially expandable ribs connectedat their distal ends to a central hub; a stem connected to and extendingdistally from the central hub, wherein the stem is adapted to space thecentral hub of the device a selected distance from a wall of aventricle; and a plurality of anchor elements attached to a plurality ofthe ribs at their proximal ends, the anchor elements being adapted tosecure the device to the wall of the ventricle of the heart; and whereinthe device is adapted to reduce a volume of the ventricle to improve apressure-volume relationship of the ventricle of the heart.
 44. Adiastolic recoil device comprising a plurality of radially expandableribs connected at their distal ends to a central hub and a membranecoupled to the ribs, the device being adapted to be deliveredpercutaneously to and anchored within the interior of a ventricle of apatient's heart to span a region of the ventricle, the radiallyexpandable ribs being adapted to deform from a first shape to a secondshape during systole and to return to the first shape a selected pointafter diastole begins to assist in expansion of the ventricle.
 45. Thedevice of claim 44, further comprising anchor elements on proximal endsof the ribs for anchoring the device to a selected area of a wall of theventricle.
 46. The device of claim 44, further comprising a contactmember extending distally from the central hub along a centrallongitudinal axis of the device, wherein the contact member is adaptedto space the central hub of the device a selected distance from a wallof the ventricle.
 47. The device of claim 44, further comprising adelayed release spring mechanism adapted to release an elastic recoilforce back to the wall of the ventricle at a selected time intervalsduring diastole.